diff --git a/math/openblas/Makefile b/math/openblas/Makefile
index 3815b2d7dfe9..2934de8d5027 100644
--- a/math/openblas/Makefile
+++ b/math/openblas/Makefile
@@ -81,6 +81,7 @@ TARGET_CPU_ARCH=	PPCG4
 .endif
 
 .if ${ARCH} == powerpc64le
+CFLAGS+=		-lm
 USE_GCC=		yes
 .endif